Field of the Invention
The present invention relates to an amphoteric ion-type basic amino acid derivative that demonstrates a gelling ability in a water system.
Discussion of the Background
A method of controlling fluidity of compositions that are liquid at ambient temperature such as cosmetic agents, pharmaceuticals, agricultural chemicals, feeds, fertilizers, paints and the like, and processing them into a form fitted for diversified use objects is an industrially very important technique. When the fluidity of an aqueous composition is controlled, water-soluble polymers such as carboxyvinyl polymer, xanthan gum and the like are generally used. These compounds are poor in salt tolerance and acid resistance, and often have difficulty in gelling an aqueous composition containing a salt or an acid. While a water-soluble polymer needs to be homogeneously dissolved or dispersed when gelling an aqueous composition, water-soluble polymers are not easily dispersed in an aqueous composition and precipitate is sometimes produced.
On the other hand, while patent document 1 discloses that sugar derivative gels water containing an oil solution and alcohol, it does not describe gelling of an aqueous composition containing a salt or an acid. Patent document 2 discloses a gelling agent of a basic amino acid derivative. While this gelling agent can gel various solvents including organic solvents, no description is provided as to aqueous solution containing an acid.
Moreover, non-patent documents 1 and 2 disclose gelling ability of amino acid derivatives having a pyridinium salt structure. While these compounds can gel even an aqueous solution containing an acid or a salt, since they are cationic molecules, they show poor compatibility with anionic water-soluble polymers such as xanthan gum, carboxyvinyl polymer and the like, and have stability problem since precipitation occurs and water is separated from the obtained gel composition.